Light stressed plant goes middle yellow rust leaves

That soil looks like it has next to zero aeration and poor drainage, too. a soil should have 50% perlite or similar and something like coco need 33% of volume. That includes anything that comes in the bag already. leaves look glossy and a bit too lush in spots, so N-tox is possible. I think there's more going on than one thing in regard to ratio of nutes and concentrations of each.

Nute burn from a soil mix that is too hot, or over feeding.....,or both...........